hexagonal Cyclosilicates
Morganite
Formula Be3Al2(SiO3)6:Mn
Crystal Structure
#! Species: Morganite (Beryl)
#! System: Hexagonal (6/mmm)
#! Habit: Short prismatic to tabular, pink
hexagonal[6/mmm]:{10-10}@1.0 + {0001}@0.5 + {11-20}@0.2 | elongate(c:0.9)
hexagonal
6/mmm
{10-10} {0001} {11-20}
Quick Facts
Hardness
7.5
Specific Gravity
2.67
Refractive Index
1.577
Optical Character
Uniaxial -
Physical Properties
- Crystal System
- hexagonal
- Hardness (Mohs)
- 7.5
- Specific Gravity
- 2.67
- Cleavage
- Imperfect basal
- Fracture
- Conchoidal to uneven
- Lustre
- Vitreous
Optical Properties
- Refractive Index
- 1.577
- Birefringence
- 0.005-0.009
- Optical Character
- Uniaxial -
- Dispersion
- 0.014
- Pleochroism
- weak: Pale pink / Deeper pink (Subtle; requires well-saturated stone to observe)
- Fluorescence
- Weak pink in some specimens
Characteristics
Colours
PinkPeachSalmonRoseLight pinkOrange-pink
Localities
BrazilMadagascarAfghanistanMozambiqueCalifornia (USA)Namibia
Common Inclusions
Liquid feathersGrowth tubesTwo-phase inclusionsMineral crystals
Known Treatments
Heat treatment (removes yellow, enhances pink)
Crystal Forms
hexagonal_prismpinacoiddihexagonal_prism
Related Minerals
Other minerals in the hexagonal system
